Abstract: A quick open-closed device for biochemical equipment (1) comprises a socket (2) disposed on the biochemical equipment and a plug (3) for coupling with the socket. The socket is a hollow, cylindrical element, and comprises a cylindrical sidewall (25) and a passage (26) in communication with an interior chamber of the biochemical equipment. The cylindrical sidewall of the socket defines an engaging slot (27), which comprises a guiding portion (271) and a retaining portion (272) connected with each other. The plug has a straight pin (31) for being inserted into the passage of the socket. A peg (312) is provided on the straight pin for rotatively and releasably engaging with the engaging slot of the socket to assembly the plug and the socket together as a unit.